Culture : The Princess and the Pearl : * Suddenly, it’s fashionable to wear the ‘world’s oldest gem’ in Japan. The long-dormant domestic market is booming, thanks in large part to a woman nicknamed Kiko-san.

For centuries, the iridescent pearl has been a subject of legend and mystery. Greeks thought they were the teardrops of mermaids. Byzantium’s rulers believed they were drops of the moon. Medieval Europeans used pearls to reflect the glare of evil spirits, while in the Far East, the gems were crushed into medicines to cure diseases.

Pearls are even said to have altered the course of history. Legend has it that Julius Caesar undertook the conquest of the British Isles because fine pearls were rumored to be found there. And pearls were the first Japanese product “traded” with the United States--though the gems were turned over under the guns of Commodore Matthew C. Perry’s black ships in 1853.

“As sure as prostitution is the oldest profession, pearls are the oldest (valued) gem,” says Ryo Yamaguchi, managing director of Mikimoto Co., Japan’s largest and most influential pearl company. And today, thanks to Mikimoto cultivation techniques, pearls are also the most plentiful gem in the world.

This wasn’t always the case. Pearls were in short supply before Kokichi Mikimoto’s patented technique--essentially producing natural pearls from oysters seeded with an artificial irritant--ran out after World War II. But then, other Japanese firms jumped into the market, and both production and demand have soared.

Now, Japan alone produces over 77 tons of pearls a year--70%-80% of the world’s total--making it the pearl capital of the world. (Other principal producing countries include Australia, Myanmar, China, Indonesia, the Philippines, and Tahiti.) Tokyo-based Mikimoto reports that its sales for the past two years have been growing at a double-digit rate.

Yamaguchi expects the Japanese share of the pearl market to rise even further because the largest natural pearl production region--in the Persian Gulf--was spoiled by oil spills during the recent war. (Natural pearls only account for about 1% of all pearl production, however.)

Contributing further to the new demand has been the renewed popularity of pearls among some of the world’s wealthiest and most photographed women, who traditionally set trends. Diana, the Princess of Wales, for example, has her simple strings, and Barbara Bush her three-strand choker. But none has popularized pearls as much as Princess Kiko--the pearl-loving Japanese commoner who charmed her nation last June with a storybook wedding to the emperor’s second son.

Kiko-san, as she is called, spurred a pearl boom so large among 18- to 24-year-old women in Japan that companies such as Mikimoto are finding that for the first time in the country’s history, it is more profitable to keep pearls at home than to ship them abroad.

Japanese companies are now exporting only 12% of their pearls abroad. The rest of the pearls are kept for sale in the domestic jewelry market, which is second only to that of the United States.

Although the coves of Japan have always been one of the world’s greatest sources of pearls, jewelry has never before played much of a role in Japanese culture. In fact, pearls were valued only in foreign trade until the 20th Century, when Japanese women began to copy Western style and adorned themselves with these and other gems.

In fact, about the only threat to Japan’s cultured pearl market now comes from half the world away, in America’s Tennessee and Mississippi rivers. Those waterways are the source of the favorite irritant inserted into an oyster to form the core of a cultured pearl--a tiny fragment of a pig-toe mussel shell.

The pig-toe is particularly valuable because its shell provides a rich source of calcium for the pearl oysters, which digest small parts of the irritant as they make the gems. Japanese companies pay $2.50 to $3 a pound for the shells, netting Tennessee divers alone an estimated $44 million last year. But the pig-toe shells are getting scarce.

There are basically three types of pearls: natural, cultured and fake.

-- Natural, also called “real” and “Oriental” pearls, are formed randomly by free oysters. A natural irritant such as sand or seaweed forms the heart of the pearl.

Japanese pearl fisheries existed more than 2,000 years ago, according to folk tales that usually tell of beautiful and seductive young women divers, who are often pictured draped in traditional white cotton gowns. The women used to dive for pearls found on coral reefs at depths of up to 70 feet.

Usually working out of small boats, they collected the oysters in bags which were opened with great anticipation at the end of the day. The divers, considered by some to be as bewitching as mermaids, also brought to the surface stories about monsters of the deep, which undoubtedly contributed to the value and the legend of pearls.

The young women divers have now largely been put out of work by cultured pearls. Mostly they harvest seaweed or may be called upon to rescue pearl oyster rafts after a storm has blown them off their anchors.

-- Cultured pearls are produced mainly in oyster beds that are suspended by rafts. The rafts are frequently transferred to different regions of the sea to protect them from red tides, typhoons, abnormally cold or warm waters and other natural dangers. Good quality pearls take at least two years to grow inside the mother oyster. The pearl farm has cared for these oysters for three or four years before implanting an artificial irritant.

The only way to tell the difference between a natural and cultured pearl is by X-raying the gem. Because no one ever checks the core, natural and cultured pearls are priced by the same standards of size, weight, luster and color.

Because Japanese oysters are relatively small, the country’s cultured pearls also tend to be smaller than those grown, for example, in the South Pacific. Also, although the Japanese might be limited to implanting two or three artificial irritants in a single oyster, South Seas oysters will accept more.

-- Fake pearls mostly come out of paste-pots and chemistry labs. The best fakes are coated with a pearly substance found in fish scales. The more coats, the more iridescence--and the more expensive the fake pearl.

While Japan now stands astride the global pearl business, the distinction of having been the first producers of cultured pearls belongs to the ancient Chinese. According to 13th-Century Chinese records, Ye Jinyang discovered that pearl production in the freshwater mussel could be stimulated by introducing a foreign object inside its shell.

The Chinese developed the technique of inserting mud, wood, bone or metal and returning the mussel to its bed for about three years to wait for the pearl. Sometimes tiny metal statues of the seated Buddha were inserted into the mussel, which would cover the Buddha with layers of nacre, which is secreted by the oyster. The pearls, shaped in the form of Buddha, were used to decorate temples and were carried as charms.

Kokichi Mikimoto is credited with discovering the technique of culturing pearls in oysters at the end of the 19th Century, but the credit should go to his son-in-law. Mikimoto’s daughter married the most advanced researcher of a competitor, who came to work for Mikimoto and produced the first cultivated pearl from an oyster rather than a mussel.

Mikimoto did score important advances in the field, however, by perfecting round (rather than lopsided) pearls, adapting implantation practices from dentists.

The Japanese still take pride in what they describe as their special feel for, and understanding of, the pearl.

Jewel specialist Shohe Shirai, for example, says it’s more difficult for the untrained eye to appraise pearls than other gems. He advises examining pearls in natural sunlight before 10 a.m., while facing north, with the pearls on a gray cloth. The price often depends on size rather than quality, so buyers should take a pearl’s luster, color, surface texture and shape into account, he says.

Although buyers can find quality pearls at top jewelry stores in Tokyo, many of the best pearls are kept by local farmers and sold in their own shorefront stores at much better prices than in city stores.

Near Toba in far southeastern Japan, pearl farmers and merchants take great pride in businesses that have been passed down through generations. Eijiro Matsui, for example, operates a wood-framed shop that stands just a narrow road away from the sea where his pearl rafts float.

Matsui, whose grandfather is said to have been the first pearl farmer in Japan to sell pearls directly to tourists rather than to the major jewelry companies, says that as a matter of family honor, pearl quality is more important to him than huge sales.

“Here, pearls are more than a product,” says Matsui, “they are a tradition.”

The Organic Gem Pearls were the first Japanese product to be traded with the United States, beginning in 1853. Today, Japan dominates the market.

1990 U.S. Imports of Cultured Pearls:

In Millions of dollars

TOTAL: 85.8

JAPAN: 62.9

AUSTRALIA: 6.3

HONG KONG: 6.3

TAIWAN: 2.3

CHINA: 0.8

SWITZERLAND: 0.2

OTHER: 6.8

How Pearls Are Formed

Oysters and other shell-forming mollusks produce a special substance called nacre or mother-of-pearl, a form of calcium carbonate. When a foreign object, such as a grain of sand, enters the shell; the nacre cells begin to work. They layer the object with successive thin sheets of nacre until the entire object is enclosed in the carbonate, forming a natural pearl. These “real” or “Oriental” pearls are formed randomly. Cultured pearls are aided by the human hand. Small spheres are cut from mother-of-pearl or other shells, wrapped in a piece of mantle cut from a fresh oyster and then inserted into small oysters. The oysters are left to grow in quiet bays until the pearl forms, about 2-7 years. Imitation pearls are made of plastices or by coating glass beads. The best fakes are coated with an iridescent substance found in fish scales.

Source: Commerce Department, World Book Encyclopedia and Encyclopedia Americana